This invention pertains to a method of assembling a well production and sand control system in unconsolidated, petroliferous formations. Basically, this invention solves the problem of a method for assembling a system for preventing cave-in and sloughing during drilling, enlargement, i.e., underreaming, gravel and screen placement and/or linear placement.
It is most desirable to utilize a large gravel or sand pack. The larger the sand pack, the more surface is available for sand pack drainage and for filtering for increased production of oil from the well. To form a large gravel pack, increased underreaming of the open hole below the casing for forming a larger cavity is required. Thus in unconsolidated sand formation the result is formation caving-in and sloughing thereof and during the subsequent steps of forming and placing the sand pack and screen and/or liner placement.
For solving this problem, the disclosed invention includes the novel feature or method steps for forming and assembling a system or apparatus for maintaining the sides of the unconsolidated formation under high positive pressure at all times from the time the high pressure fluid jetting starts forming the cavity in the well until a sand pack is completed for production of the well. This problem is prevalent, for example, from the formerly Texaco Slocum Field (bought in about 1902) in Anderson County, Texas to the Athabasca Tar Sands of Canada.